diff --git a/__tests__/test-utils/index.js b/__tests__/test-utils/index.ts
similarity index 78%
rename from __tests__/test-utils/index.js
rename to __tests__/test-utils/index.ts
index 4c5466f88..e562441af 100644
--- a/__tests__/test-utils/index.js
+++ b/__tests__/test-utils/index.ts
@@ -1,8 +1,8 @@
 // Sun Aug 04 2019 19:34:56 GMT-0700
 const DEFAULT_TEST_TIME = Date.UTC(2019, 7, 5, 2, 34, 56, 78)
 
-export function timeoutPromise (ms) {
-  return new Promise((resolve, reject) => {
+export function timeoutPromise(ms: number): Promise<void> {
+  return new Promise((resolve) => {
     setTimeout(resolve, ms)
   })
 }
@@ -17,7 +17,7 @@ export function timeoutPromise (ms) {
  * https://stackoverflow.com/a/42787232/915811 (basically, moment.js uses
  * Date#now internally).
  */
-export function setTestTime (time) {
+export function setTestTime(time: number): void {
   const date = new Date(time)
   // Log human-readable date to help out human testers.
   console.log(`Setting test time to ${date}`)
@@ -28,7 +28,7 @@ export function setTestTime (time) {
  * Sets the default mock test time for a variety of tests such that various
  * calculations and feed version statuses resolve to a certain state.
  */
-export function setDefaultTestTime () {
+export function setDefaultTestTime(): void {
   setTestTime(DEFAULT_TEST_TIME)
 }
 
@@ -36,6 +36,7 @@ export function setDefaultTestTime () {
  * Restore the standard functionality of Date library. This should be used in
  * the afterEach clause in test suites that require a mocked date.
  */
-export function restoreDateNowBehavior () {
-  Date.now.mockRestore && Date.now.mockRestore()
+export function restoreDateNowBehavior(): void {
+  const now = Date.now as jest.Mock
+  now.mockRestore && now.mockRestore()
 }
diff --git a/__tests__/util/itinerary.js b/__tests__/util/itinerary.js
deleted file mode 100644
index 61452f0be..000000000
--- a/__tests__/util/itinerary.js
+++ /dev/null
@@ -1,152 +0,0 @@
-/* globals describe, expect, it */
-
-import {
-  getItineraryDefaultMonitoredDays,
-  itineraryCanBeMonitored
-} from '../../lib/util/itinerary'
-import { WEEKDAYS, WEEKEND_DAYS } from '../../lib/util/monitored-trip'
-
-const walkLeg = {
-  mode: 'WALK'
-}
-
-describe('util > itinerary', () => {
-  describe('itineraryCanBeMonitored', () => {
-    const transitLeg = {
-      mode: 'BUS',
-      transitLeg: true
-    }
-    const rentalBikeLeg = {
-      mode: 'BICYCLE_RENT',
-      rentedBike: true
-    }
-    const rentalCarLeg = {
-      mode: 'CAR_RENT',
-      rentedCar: true
-    }
-    const rentalMicromobilityLeg = {
-      mode: 'MICROMOBILITY_RENT',
-      rentedVehicle: true
-    }
-    const rideHailLeg = {
-      hailedCar: true,
-      mode: 'CAR_HAIL'
-    }
-
-    const testCases = [{
-      expected: true,
-      itinerary: {
-        legs: [transitLeg, walkLeg]
-      },
-      title: 'should be true for an itinerary with transit, no rentals/ride hail.'
-    }, {
-      expected: false,
-      itinerary: {
-        legs: [walkLeg, rentalBikeLeg]
-      },
-      title: 'should be false for an itinerary without transit.'
-    }, {
-      expected: false,
-      itinerary: {
-        legs: [walkLeg, transitLeg, rentalBikeLeg]
-      },
-      title: 'should be false for an itinerary with transit and rental bike.'
-    }, {
-      expected: false,
-      itinerary: {
-        legs: [walkLeg, transitLeg, rentalCarLeg]
-      },
-      title: 'should be false for an itinerary with transit and rental car.'
-    }, {
-      expected: false,
-      itinerary: {
-        legs: [walkLeg, transitLeg, rentalMicromobilityLeg]
-      },
-      title: 'should be false for an itinerary with transit and rental micromobility.'
-    }, {
-      expected: false,
-      itinerary: {
-        legs: [walkLeg, transitLeg, rideHailLeg]
-      },
-      title: 'should be false for an itinerary with transit and ride hail.'
-    }, {
-      expected: false,
-      itinerary: {},
-      title: 'should be false for a blank itinerary.'
-    }, {
-      expected: false,
-      itinerary: null,
-      title: 'should be false for a null itinerary.'
-    }]
-
-    testCases.forEach(({ expected, itinerary, title }) => {
-      it(title, () => {
-        expect(itineraryCanBeMonitored(itinerary)).toBe(expected)
-      })
-    })
-  })
-  describe('getItineraryDefaultMonitoredDays', () => {
-    const transitLegWeekday = {
-      mode: 'BUS',
-      serviceDate: '20210609', // Wednesday
-      transitLeg: true
-    }
-    const transitLegSaturday = {
-      mode: 'BUS',
-      serviceDate: '20210612', // Saturday
-      transitLeg: true
-    }
-    const transitLegSunday = {
-      mode: 'BUS',
-      serviceDate: '20210613', // Sunday
-      transitLeg: true
-    }
-
-    const testCases = [{
-      expected: WEEKDAYS,
-      itinerary: {
-        legs: [walkLeg, transitLegWeekday]
-      },
-      title: 'should be [\'monday\' thru \'friday\'] for an itinerary starting on a weekday.'
-    }, {
-      expected: WEEKEND_DAYS,
-      itinerary: {
-        legs: [walkLeg, transitLegSaturday]
-      },
-      title: 'should be [\'saturday\', \'sunday\'] for an itinerary starting on a Saturday.'
-    }, {
-      expected: WEEKEND_DAYS,
-      itinerary: {
-        legs: [walkLeg, transitLegSunday]
-      },
-      title: 'should be [\'saturday\', \'sunday\'] for an itinerary starting on a Sunday.'
-    }, {
-      expected: WEEKDAYS,
-      itinerary: {
-        legs: [walkLeg],
-        startTime: 1623341891000 // Thursday 2021-06-10 12:18 pm EDT
-      },
-      title: 'should be [\'monday\' thru \'friday\'] for an itinerary without transit starting on a weekday (fallback case).'
-    }, {
-      expected: WEEKEND_DAYS,
-      itinerary: {
-        legs: [walkLeg],
-        startTime: 1623514691000 // Saturday 2021-06-12 12:18 pm EDT
-      },
-      title: 'should be [\'saturday\', \'sunday\'] for an itinerary without transit starting on a Saturday (fallback case).'
-    }, {
-      expected: WEEKEND_DAYS,
-      itinerary: {
-        legs: [walkLeg],
-        startTime: 1623601091000 // Sunday 2021-06-13 12:18 pm EDT
-      },
-      title: 'should be [\'saturday\', \'sunday\'] for an itinerary without transit starting on a Sunday (fallback case).'
-    }]
-
-    testCases.forEach(({ expected, itinerary, title }) => {
-      it(title, () => {
-        expect(getItineraryDefaultMonitoredDays(itinerary)).toBe(expected)
-      })
-    })
-  })
-})
diff --git a/__tests__/util/itinerary.ts b/__tests__/util/itinerary.ts
new file mode 100644
index 000000000..526d3edf0
--- /dev/null
+++ b/__tests__/util/itinerary.ts
@@ -0,0 +1,176 @@
+/* globals describe, expect, it */
+
+import {
+  getItineraryDefaultMonitoredDays,
+  itineraryCanBeMonitored
+} from '../../lib/util/itinerary'
+import { WEEKDAYS, WEEKEND_DAYS } from '../../lib/util/monitored-trip'
+
+const walkLeg = {
+  mode: 'WALK'
+}
+
+describe('util > itinerary', () => {
+  describe('itineraryCanBeMonitored', () => {
+    const transitLeg = {
+      mode: 'BUS',
+      transitLeg: true
+    }
+    const rentalBikeLeg = {
+      mode: 'BICYCLE_RENT',
+      rentedBike: true
+    }
+    const rentalCarLeg = {
+      mode: 'CAR_RENT',
+      rentedCar: true
+    }
+    const rentalMicromobilityLeg = {
+      mode: 'MICROMOBILITY_RENT',
+      rentedVehicle: true
+    }
+    const rideHailLeg = {
+      hailedCar: true,
+      mode: 'CAR_HAIL'
+    }
+
+    const testCases = [
+      {
+        expected: true,
+        itinerary: {
+          legs: [transitLeg, walkLeg]
+        },
+        title:
+          'should be true for an itinerary with transit, no rentals/ride hail.'
+      },
+      {
+        expected: false,
+        itinerary: {
+          legs: [walkLeg, rentalBikeLeg]
+        },
+        title: 'should be false for an itinerary without transit.'
+      },
+      {
+        expected: false,
+        itinerary: {
+          legs: [walkLeg, transitLeg, rentalBikeLeg]
+        },
+        title: 'should be false for an itinerary with transit and rental bike.'
+      },
+      {
+        expected: false,
+        itinerary: {
+          legs: [walkLeg, transitLeg, rentalCarLeg]
+        },
+        title: 'should be false for an itinerary with transit and rental car.'
+      },
+      {
+        expected: false,
+        itinerary: {
+          legs: [walkLeg, transitLeg, rentalMicromobilityLeg]
+        },
+        title:
+          'should be false for an itinerary with transit and rental micromobility.'
+      },
+      {
+        expected: false,
+        itinerary: {
+          legs: [walkLeg, transitLeg, rideHailLeg]
+        },
+        title: 'should be false for an itinerary with transit and ride hail.'
+      },
+      {
+        expected: false,
+        itinerary: {},
+        title: 'should be false for a blank itinerary.'
+      },
+      {
+        expected: false,
+        itinerary: null,
+        title: 'should be false for a null itinerary.'
+      }
+    ]
+
+    testCases.forEach(({ expected, itinerary, title }) => {
+      it(`${title}`, () => {
+        expect(itineraryCanBeMonitored(itinerary)).toBe(expected)
+      })
+    })
+  })
+  describe('getItineraryDefaultMonitoredDays', () => {
+    const transitLegWeekday = {
+      mode: 'BUS',
+      serviceDate: '20210609', // Wednesday
+      transitLeg: true
+    }
+    const transitLegSaturday = {
+      mode: 'BUS',
+      serviceDate: '20210612', // Saturday
+      transitLeg: true
+    }
+    const transitLegSunday = {
+      mode: 'BUS',
+      serviceDate: '20210613', // Sunday
+      transitLeg: true
+    }
+
+    const testCases = [
+      {
+        expected: WEEKDAYS,
+        itinerary: {
+          legs: [walkLeg, transitLegWeekday]
+        },
+        title:
+          "should be ['monday' thru 'friday'] for an itinerary starting on a weekday."
+      },
+      {
+        expected: WEEKEND_DAYS,
+        itinerary: {
+          legs: [walkLeg, transitLegSaturday]
+        },
+        title:
+          "should be ['saturday', 'sunday'] for an itinerary starting on a Saturday."
+      },
+      {
+        expected: WEEKEND_DAYS,
+        itinerary: {
+          legs: [walkLeg, transitLegSunday]
+        },
+        title:
+          "should be ['saturday', 'sunday'] for an itinerary starting on a Sunday."
+      },
+      {
+        expected: WEEKDAYS,
+        itinerary: {
+          legs: [walkLeg],
+          startTime: 1623341891000 // Thursday 2021-06-10 12:18 pm EDT
+        },
+        title:
+          "should be ['monday' thru 'friday'] for an itinerary without transit starting on a weekday (fallback case)."
+      },
+      {
+        expected: WEEKEND_DAYS,
+        itinerary: {
+          legs: [walkLeg],
+          startTime: 1623514691000 // Saturday 2021-06-12 12:18 pm EDT
+        },
+        title:
+          "should be ['saturday', 'sunday'] for an itinerary without transit starting on a Saturday (fallback case)."
+      },
+      {
+        expected: WEEKEND_DAYS,
+        itinerary: {
+          legs: [walkLeg],
+          startTime: 1623601091000 // Sunday 2021-06-13 12:18 pm EDT
+        },
+        title:
+          "should be ['saturday', 'sunday'] for an itinerary without transit starting on a Sunday (fallback case)."
+      }
+    ]
+
+    testCases.forEach(({ expected, itinerary, title }) => {
+      it(`${title}`, () => {
+        expect(getItineraryDefaultMonitoredDays(itinerary)).toBe(expected)
+      })
+    })
+  })
+})